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                                                                    EXHIBIT 4.10

[OSI LOGO]

February 28, 2005

MAPCON MAPPING CONSULTANTS INC.
PHILLIP FLOOR & STEVEN FLOOR
4545 South 2300 East
Salt Lake City
Utah 84117

Dear Sirs:

RE:   BINDING LETTER OF INTENT TO PURCHASE SHARES OF Mapcon Mapping Consultants
      Inc. ("MAPCON")

Further to our recent correspondence and discussions, this letter constitutes a
binding offer by Offshore Systems International Ltd. ("OSIL") to purchase all of
the issued and outstanding shares of Mapcon Mapping Consultants Inc. (the
"Mapcon Shares").

OSIL's offer set out in this letter is conditional only upon the preparation of
a mutually satisfactory Definitive Agreement and final approval of OSIL's board
of directors.

BACKGROUND

This offer is made by OSIL based upon the following understandings:

      (a)   Mapcon is a privately owned Utah corporation;

      (b)   Phillip Floor and Steven Floor (the "Shareholders") are and will on
            closing be the registered and beneficial owners of 100% of the
            issued and outstanding Mapcon Shares, each as to 50%. No other party
            has any right or option by way of exercise, conversion or otherwise,
            to acquire any of the Mapcon Shares or any un-issued securities in
            the capital of Mapcon;

      (c)   There will be no material adverse change in the business or affairs
            of Mapcon between the projected financial statements for the period
            ended December 31, 2004 as set out in the e-mail dated November 05,
            2004 2:06 PM from Gary Manzer to Steve Floor (doc@mapcomapping.com)
            and Phillip Floor (phil@mapcomapping.com), attached hereto for
            reference, and closing.

INTENT TO PURCHASE SHARES

OSIL offers to purchase the Mapcon Shares. OSIL reserves the right to purchase
the Mapcon Shares directly or through an affiliated or subsidiary entity or a
combination thereof. The obligation of

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payment remains with OSIL. The purchase of the Mapcon Shares will be subject to
the following terms and conditions:

1.    PURCHASE PRICE

      The total purchase price (the "PURCHASE PRICE") will be one million United
      States dollars (USD$1,000,000) including the shares described in section
      2(b), subject to adjustment in accordance with section 3. All dollar
      amounts referred to in this letter will mean US dollars unless otherwise
      stipulated.

2.    TERMS OF PAYMENT AND ALLOCATION OF PURCHASE PRICE

      The Purchase Price will be paid and satisfied as follows:

      (a)   By payment of USD$950,000 to the Shareholders in cash as follows:

            (i)   USD$530,000 to be paid by certified cheque, bank draft or wire
                  transfer on closing, in accordance with the Definitive
                  Agreement; and

            (ii)  USD$300,000 to be paid to the Shareholders, subject to
                  adjustment and escrow in accordance with sections 3 and 4(b);
                  and

            (iii) USD$120,000 to be paid to the Shareholders subject to
                  adjustment and escrow in accordance with sections 3c and 4(b);

      (b)   By the issuance to the Shareholders of shares on closing in the
            capital of OSIL with an aggregate value of USD$50,000 (the "OSIL
            Shares"). The number of OSIL shares to be issued will be determined
            by dividing USD$50,000 by the average 30 day trading price of OSIL's
            common shares prior to the date on which the Definitive Agreement is
            signed. The trading price for OSIL's shares is quoted in Canadian
            dollars. The average exchange rate (quoted by the Bank of Canada)
            over the same 30 day period will be used for converting Canadian
            dollars to US dollars.

3.    HOLDBACK AND ADJUSTMENTS

      (a)   A total of $300,000 of the cash portion of the Purchase Price
            payable on closing will be held in escrow for a period of ninety
            (90) days following closing, pending the making of final working
            capital adjustments, based on Background item (c), and financial
            statements prepared at the closing date that are prepared on a
            consistent basis with those referenced in Background item (c). The
            parties will act with reasonable diligence and in good faith to
            finalize such adjustments within a reasonable time period. Any net
            adjustments in favour of OSIL will be deducted from the holdback,
            and the balance of the holdback remitted to the Shareholders within
            ninety (90) days. Any net adjustments in favour of the Shareholders
            will be paid to the Shareholders promptly upon completion of the
            adjustment calculations, and the holdback paid to the Shareholders .
            In no event shall such working capital adjustments reduce the
            purchase price without the consent of the shareholders.

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      (b)   A total of $120,000 of the cash portion of the Purchase Price
            payable on closing will be held back until the award to Mapcon of
            additional Task Orders with an aggregate value of USD$300,000 by the
            United States Forest Service ("USFS") between closing and the expiry
            of USFS contract number 53-84N8-1-028 dated July 27, 2001
            (understood to be 26 July, 2006). The amount of Additional Task
            Orders received from the USFS will be reviewed every three months at
            the end of May, August, November, and February and a pro rata
            portion of the held back amount will be released by the end of the
            following month.

4.    HOLD PERIODS AND ESCROW PROVISIONS

      (a)   Mapcon and the Shareholders acknowledge that the common shares of
            OSIL are listed for trading on the TSX in Canada and are also quoted
            for trading on the "OTCBB" in the United States. The OSIL Shares
            will be issued to the Shareholders subject to such trading
            restrictions, hold periods, escrow and reporting requirements as are
            imposed under applicable securities laws, including the laws of
            Canada and its Provinces, as applicable, and the laws of the United
            States and the State(s) in which the Shareholders are residents, and
            in accordance with the policies of the TSX. OSIL will endeavour to
            maintain TSX status.

      (b)   The cash holdbacks for the purchase of Mapcon Shares, shall be
            subject to the escrow terms as agreed by the parties in the
            Definitive Agreement.

5.    NO ENCUMBRANCES

      On closing the Shareholders will deliver good title to the Mapcon Shares
      to OSIL free and clear of any and all liens, charges, encumbrances and
      adverse claims whatsoever.

6.    REGULATORY APPROVAL

      The parties acknowledge that the transactions contemplated hereby shall be
      subject to the approval of the TSX and all other regulatory authorities
      having jurisdiction. Without limiting the generality of the foregoing, the
      parties acknowledge that the number and deemed price of the OSIL Shares to
      be issued to the Shareholders is subject to TSX approval. OSIL agrees that
      promptly upon execution of the Definitive Agreement referred to in section
      10, it shall make application to the TSX and use its reasonable efforts to
      obtain such approval as soon as reasonably practicable. Mapcon and the
      Shareholders agree to co-operate with OSIL and provide all information and
      documentation as the TSX may reasonably request in support of OSIL's
      application for approval.

7.    EMPLOYMENT AND CONSULTING AGREEMENTS

      The completion of the purchase of the Mapcon Shares will be subject to
      Mapcon entering into employment, management or consulting agreements with
      current senior management of Mapcon (to take effect on closing) on terms
      and conditions satisfactory to all parties.

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8.    CONFIDENTIALITY

      OSIL and Mapcon acknowledge that they have entered into a mutual
      confidentiality agreement dated July 20, 2004 (the "NDA").

9.    STAND-STILL AGREEMENT

      Mapcon and the Shareholders agree that none of them will engage in
      negotiations or discussions with any party other than OSIL and its
      representatives respecting a possible sale of the Mapcon Shares, a sale of
      the assets of Mapcon, or any other merger or business combination
      respecting Mapcon unless the parties fail to conclude a definitive
      agreement by March 31, 2005.

10.   PREPARATION OF AGREEMENT -

      The parties will use their reasonable best efforts to enter into a formal
      agreement (the "Definitive Agreement") encompassing the subject matter
      hereof and other provisions which are typical and customary for
      transactions of like nature within 30 days, with an anticipated closing
      date of March 14, 2005.

11.   EXPENSES

      Each of OSIL and Mapcon shall be responsible for its own legal, consulting
      and other costs and expenses incurred by it with respect to this letter of
      intent and the formal agreements contemplated by this letter of intent. In
      the event that the transactions contemplated by this letter of intent do
      not result in the execution of a formal purchase and sale agreement with
      respect to the Mapcon Shares, neither party shall have any claim against
      the other (except pursuant to section 8 or section 9 of this letter of
      intent or pursuant to the NDA) as a result of such failure to reach a
      formal agreement.

      The closing audited financial statements of Mapcon shall be prepared in
      accordance with U.S. GAAP by a mutually agreed audit firm and the cost of
      such statements shall be paid equally by OSIL and Mapcon. The purpose of
      the GAAP Audit is to assign values to any holdbacks or adjustments. The
      audit fee itself is to be treated as one of the Section 3 adjustments.

12.   NEWS RELEASES

      The parties acknowledge that OSIL, as a publicly trading corporation, has
      a legal obligation to issue news releases respecting any material changes
      in its affairs and to file material change reports with securities
      regulatory authorities in Canada and the U.S. As such, OSIL may have an
      obligation to issue a news release concerning the execution of this letter
      of intent and will be required to do so with respect to any formal
      agreement in furtherance of the transactions contemplated by this letter
      of intent. OSIL agrees to deliver to a representative appointed by Mapcon
      a draft of any such news releases for review and comment by that
      representative. That representative shall have 24 hours within which to
      provide any comments concerning the draft news release. OSIL agrees to
      take the comments of such representative into account and to act
      reasonably in finalizing any news releases that it issues concerning its
      dealings with Mapcon.

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13.   GOVERNING LAW AND LANGUAGE

      The provisions of this letter which are binding on the parties (being
      sections 8, 9, 11, 12 and this section 13) shall be governed by and
      construed in accordance with the laws of the Province of British Columbia,
      without reference to its conflict of law principles and the parties agree
      to irrevocably submit to the jurisdiction of the courts of British
      Columbia with respect to any legal proceedings arising herefrom.

Please indicate your willingness to proceed on the basis outlined herein by
signing a copy of this letter and returning it to us.

Yours sincerely,

OFFSHORE SYSTEMS INTERNATIONAL LTD.

Per: /s/ "John Jacobson"
     -------------------------

     John Jacobson
     President and CEO

The foregoing proposal is hereby accepted as of the 28th day of February, 2005,
and will form the basis for proceeding with preparation of the definitive
agreement and other matters as referred to herein.

MAPCON MAPPING CONSULTANTS INC.

By: /s/ "Phillip S. Floor"
    --------------------------
    Authorized Signatory

By: /s/ "J. Steven Floor"
    --------------------------
    Authorized Signatory

SHAREHOLDERS OF MAPCON MAPPING CONSULTANTS INC.

/s/ "Phillip S. Floor"
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Phillip Floor

/s/ "J. Steven Floor"
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Steven Floor

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